Definition: An inner garment, worn next to the skin.
Equivalent of Greek chiton & Hebrew kethoneth.
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In Roman society, the tunica normally came down to just above the knee, especially for soldiers, workers & slaves. Ankle-length tunicas were known for more sedentary professions.
Women often wore an ankle-length skirt under their tunica. Although the garment was loose-fitting for men, it may have been loose or tight on women.
The tunica was adopted from the Greeks in the 3rd century BC.
Clavi
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Clavi were stripes woven into the tunica, which ran vertically from each shoulder. The wool yarn was dyed with Tyrian purple, an expensive dye that symbolized royalty & wealth.
The laticlavus was worn by senators & was approximately 3 inches (75 mm) wide.
The angusticlavus was worn by the equestrian class & was approximately one inch (25 mm) wide.
On certain occasions, particularly during times of political or social upheaval, senators in Rome chose to wear the equestrian tunic as a public display of distress.